Don’t Believe the Progressive Hype

Trump’s missteps have energized the left, but tea-party comparisons are overwrought.

The first few weeks of Donald Trump’s presidency have buoyed Democrats. The ouster of National Security Adviser Mike Flynn and the furor surrounding Mr. Trump’s immigration order have energized the party’s base. Democrats believe there’s a tea-party-style movement forming that will help them sweep the 2018 midterms. Perhaps, but there are critical differences between now and 2009.

The tea party arose spontaneously as an organic display of deep disagreements with President Obama’s stimulus bill. ObamaCare strengthened the opposition,...